1 Human development is the scientific study of processes of change and stability.  The scientific study of human development began with studies of childhood during the nineteenth century.
verb (used with object), cultivated, cultivating. 1. to prepare and work on (land) in order to raise crops; till. 2. to use a cultivator on. 3. to promote or improve the growth of (a plant, crop, etc.) by labor and attention.
A cultivator is a tool used for gardening and farming. When properly used, a cultivator will help keep soil healthy for the plants growing in it. Different types of cultivator are used for commercial farming and home gardening.